Wavelength Modulation Spectra and Electronic Band Structure of SnS 2 and SnSe 2

The first detailed reflectivity and differential reflectivity measurements performed on the layer compounds SnS 2 and SnSe 2 for energies ranging from 2 to 6 eV are presented. The results are discussed on the basis of existing band structure calculations. The main structures in the optical response of SnS 2 and SnSe 2 are found to result from excitations from the top most anion p‐type valence states (crystal field split p z and p xy type levels) into the lowest conduction band (anion and cation s‐ and p‐type levels). The location of these structures in k ‐space is found to be very close to symmetry determined “special k ‐points” for SnS 2 .